1. Field of the Invention
This invention relates to an antenna for a mobile transmitter and/or receiver device, in particularly for a hand-held transmitter/receiver for a wireless microphone, with a monopole or dipole antenna element.
2. Description of the Prior Art
The prior art describes a number of different antenna concepts for mobile transmitter/receiver devices. Because of the limited amount of energy (battery) that is available, the goal of these antenna concepts is to maximize the radiation efficiency with the most compact antenna possible, or with a form factor that is optimally adapted to the overall unit. Examples of antenna concepts of this type are helix, inverted-L or inverted-F antennas, as well as dipole and monopole antennas.
The dipole and monopole antennas often form a dipole in which a first arm of the antenna is formed by an electrical conductor (e.g. a connecting piece between the housing and the printed circuit board and a grip of the mobile transmitter and/or receiver device) (monopole), and a second arm is formed by a virtual electrical mirror image with inverted polarity of the first arm (of the monopole antenna) in one or more electrical reference planes (e.g. the ground plane(s) in a circuit board or in circuit boards, which can also house the electronics. These circuit boards, for example, can on one hand lie in the same axis as the grip and on the other hand can be perpendicular to the housing connecting piece, and thereby fix an essential part of the monopole antenna in position. In this configuration, the feed point of the antenna lies between the grip and printed circuit board in the connecting piece.